Improvement in blasting-squibs



T. s. THOMAS & J. R.'POWELL.

Blasting-Squib No. 220,735.

C%W%%W WITNESSES:

' INVENTORS.

Patented Oct. 21, I879.

ATTORNEY.

UNITED STATES-PATENT OFFICE.

THOMAS S. THOMAS AND J OHN R. POWELL, OF PLYMOUTH, PENNSYLVANIA.

IMPROVEMENT IN BLASTlNG-SQUIBS.

Specification forming partof Lettcrs PatcntNo. 220,735, dated October '21, 1819; applicatlon filed July 21, 1878.

To all whom it may (5 m.- 1

Be it known that we, T'noMAs- S. THOMAS and JOHN R. POWELL, c Plymouth, county of 'Luzerne, and State of Pennsylvania, have invented certain new and useful Improvements in Mining-Squibs for Blasting'Coal and Rock; and we do herebydeclare that the following is a'full, clear, and exact description of the invention, that will enable others skilled in the art to which it appertains to make and use the same, reference being bad to the accompanying drawing, and to the letters and ti gures' of reference marked thereon, which form a part of this specification.

The sameletters and figures of reference are used to indicate the correspondingparts.-

After describing our invention, its nature and extcnt will be 'shown in the claims.

material which will burn only when brought into contact with a bright flame. Any substance that would burn, or even hold dead-- fire when brought in contact with a live coal, 1 would be unsuitable as a stopper for the upper. end of the squib.- A slow-match is attached tothe upper end oft-he squib. *This.

match consist-sot a small roll of twisted paper saturated with any suitablecomposition which will cause the match to burn with a slow bright flame until the the squib isreached. Any composition that would carry dead-fire or would burn with a coal would be an improper composition with which to saturate the match. V

The composition should not be brittle, like sulphur, as that substance is liable to break on, and thus allow the paper, when the sulphur is removed, to carry dead-fire. A brittle composition will allow: the match to become untwisted. so that the powder will run down'in sulphur in the end of the matcln'and thus discharge the blast .prematurely. A composition of bees-wax, brown sugar, and starch will answer these conditionsv of a good slow-match.

The match may be made so as to fit sqiiibs' Q of'any given size, and attached to the squib when needed; or'the match-may be loosely attached to the squib and then dipped in the inflammable composition, so that the attachnient will become firm.

1n the drawings, .0 is the match; D, the tube; B, the sulphur or the composition 'at the upper end, and A the soap at the lower end.

Squibs of straw or other water-proof material havebeen usedbefore; and alsoslow matches in connection with squibs have before been used; but/the upper ends of sqnilos have not before been closed, so as to prevent" the powder therein from running down. into the match when the match becomes partially untwisted. This causes the premature explosion of the blast-,and' is the cause of many accidents in mining.- i

The object of our invention is to provide a squib which will avoid the danger from deadfire, and also the danger from premature explosions, as herein described.

Having now fully described our invention, what we claim, and desire to secure by Letters Patent, is-

1. In a mining-squib, a water-proof tube closed at its upper end with sulphur or any similar material, in combination with the slow match, substantially as shown and described, and for the purposes herein set forth. 2. A slow-match saturated with a compositi'ou of bees-wax, starch, and sugar, or; any equivalent com position, substantially as shown and described, and for the purposes herein set forth.

Witness our hands this 23d day of July, A.

THOMAS S. THOMAS. JOHN R. POWELL. In presence of- H. QMAGEE,

J. W. Eno. 

